| BIG BUCK ENTERPRISES, INC.Plainville, CT · Active | Plainville, CT | Corporation | Jan 6, 1972 | Active |
| P & P FOOD MARKET, INC.Plainville, CT · Active | Plainville, CT | Corporation | Jun 16, 1967 | Active |
| PAGLIACCI'S RESTAURANT, INC.Plainville, CT · Active | Plainville, CT | Corporation | Nov 3, 1976 | Active |
| PAINTING & DECORATING, INC.Plainville, CT · Active | Plainville, CT | Corporation | May 18, 1973 | Active |
| PARSONS BUICK COMPANY, THEPlainville, CT · Dissolved | Plainville, CT | Corporation | Dec 23, 1952 | Dissolved |
| PERMATYPE COMPANY, INC. THEPlainville, CT · Active | Plainville, CT | Corporation | Jul 8, 1960 | Active |
| PIZZITOLA ELECTRIC CO.Plainville, CT · Active | Plainville, CT | Corporation | Dec 7, 1959 | Active |
| PLAINVILLE PLATING COMPANY, INC.Plainville, CT · Active | Plainville, CT | Corporation | Apr 2, 1975 | Active |
| PLAINVILLE MASONIC TEMPLE CORPORATION, THEPlainville, CT · Dissolved | Plainville, CT | Corporation | Feb 11, 1912 | Dissolved |
| RACE INDUSTRIES, INC.Plainville, CT · Forfeited | Plainville, CT | Corporation | Nov 14, 1975 | Forfeited |
| RO-BRAND PRODUCTS, INC.Plainville, CT · Active | Plainville, CT | Corporation | Jul 6, 1972 | Active |
| TACO PRODUCTS, INCORPORATEDPlainville, CT · Merged | Plainville, CT | Corporation | Mar 3, 1970 | Merged |
| TOPPER & GRIGGS, INCORPORATEDPlainville, CT · Forfeited | Plainville, CT | Corporation | Jan 5, 1954 | Forfeited |
| WASHINGTON CONCRETE PRODUCTS, INC.Plainville, CT · Active | Plainville, CT | Corporation | Sep 1, 1960 | Active |
| WASLEY PRODUCTS, INCORPORATEDPlainville, CT · Forfeited | Plainville, CT | Corporation | Dec 29, 1950 | Forfeited |
| WIDGER MANUFACTURING COMPANY, INC.Plainville, CT · Dissolved | Plainville, CT | Corporation | Aug 30, 1966 | Dissolved |
| PLAINVILLE POLICE ASSOCIATION, INCORPORATED, THEPlainville, CT · Active | Plainville, CT | Corporation | Mar 8, 1950 | Active |
| CHURCHILL BRIDGE ASSOCIATION (#1) INC.Plainville, CT · Active | Plainville, CT | Corporation | Oct 25, 1974 | Active |
| ASSOCIATED BUILDERS AND CONTRACTORS OF CONNECTICUT , INC.Plainville, CT · Active | Plainville, CT | Corporation | Jun 1, 1976 | Active |
| EMERGENCY MEDICAL TECHNICIANS OF CONNECTICUT, INC.Planville, CT · Forfeited | Planville, CT | Corporation | Oct 31, 1975 | Forfeited |
| HOME OWNERS ASSN. INC. OF PLAINVILLEPlainville, CT · Forfeited | Plainville, CT | Corporation | Aug 23, 1966 | Forfeited |
| GREAT PLAINS REAL ESTATE ASSOCIATION INCORPORATEDPlainville, CT · Active | Plainville, CT | Corporation | Nov 21, 1952 | Active |
| PARC, INC. PLAINVILLEPlainville, CT · Active | Plainville, CT | Corporation | May 3, 1962 | Active |
| PLAINVILLE CAMP GROUNDS ASSOCIATION, INC. THEPlainville, CT · Active | Plainville, CT | Corporation | Feb 27, 1957 | Active |
| PLAINVILLE CHAMBER OF COMMERCE, INC.Plainville, CT · Dissolved | Plainville, CT | Corporation | Nov 18, 1970 | Dissolved |
| PLAINVILLE EARLY LEARNING CENTER, INCORPORATEDPlainville, CT · Active | Plainville, CT | Corporation | Aug 14, 1969 | Active |
| PLAINVILLE FIRE COMPANY, INCORPORATED THEPlainville, CT · Active | Plainville, CT | Corporation | Jan 2, 1952 | Active |
| PLAINVILLE HISTORICAL SOCIETY, INC., THEPlainville, CT · Active | Plainville, CT | Corporation | Aug 27, 1968 | Active |
| PLAINVILLE LITTLE LEAGUE BASEBALL, INCORPORATEDPlainville, CT · Active | Plainville, CT | Corporation | Jan 18, 1951 | Active |
| ROTARY CLUB OF PLAINVILLE, INCORPORATEDPlainville, CT · Active | Plainville, CT | Corporation | Jul 11, 1974 | Active |
| FOUNDATION FOR THE ARTS AND TRAUMA, INC.Plainville, CT · Active | Plainville, CT | Corporation | May 3, 1976 | Active |
| WOMAN'S CLUB OF PLAINVILLE, INCORPORATEDPlainville, CT · Forfeited | Plainville, CT | Corporation | Aug 2, 1949 | Forfeited |
| MID-STATE ASSOCIATION OF REALTORS, INC.Plainville, CT · Active | Plainville, CT | Corporation | Nov 1, 1965 | Active |
| GNAZZO FOOD CENTER, INC.Plainville, CT · Active | Plainville, CT | Corporation | Jan 3, 1978 | Active |
| MCCUTCHEON CONCRETE, INC.Plainville, CT · Dissolved | Plainville, CT | Corporation | Jun 30, 1978 | Dissolved |
| DOMUS AMORIS, INC.Plainville, CT · Active | Plainville, CT | Corporation | Jul 6, 1978 | Active |
| D'AMICO REALTY, INC.Plainville, CT · Dissolved | Plainville, CT | Corporation | Aug 31, 1978 | Dissolved |
| DEFEO ENTERPRISES, INC.Plainville, CT · Merged | Plainville, CT | Corporation | Sep 28, 1978 | Merged |
| INSURANCE ASSOCIATES, INC.Plainville, CT · Active | Plainville, CT | Corporation | Jan 3, 1962 | Active |
| SOUTH END MOTOR CARS, INC.Plainville, CT · Active | Plainville, CT | Corporation | Aug 10, 1977 | Active |
| WALKER CRANE & RIGGING CORP.Plainville, CT · Active | Plainville, CT | Corporation | Mar 1, 1951 | Active |
| PENDIMAN CORPORATIONPlainville, CT · Dissolved | Plainville, CT | Corporation | Feb 20, 1979 | Dissolved |
| HARTFORD COUNTY FIRE EMERGENCY PLAN, INC.Plainville, CT · Active | Plainville, CT | Corporation | Sep 8, 1960 | Active |
| TETCO, INC.Plainville, CT · Active | Plainville, CT | Corporation | Jun 1, 1979 | Active |
| GARY SANTA MARIA D.M.D., P.C.Plainville, CT · Active | Plainville, CT | Corporation | Oct 2, 1979 | Active |
| WHEELER CLINIC, INC.Plainville, CT · Active | Plainville, CT | Corporation | Jan 9, 1968 | Active |
| ADAMS AND WELCH RESTAURANT ASSOCIATES, INC.Plainville, CT · Active | Plainville, CT | Corporation | Jan 24, 1980 | Active |
| HAIR SPA, INCPlainville, CT · Active | Plainville, CT | Corporation | Feb 26, 1980 | Active |
| WIDE LOAD ASSOCIATES, INC.Plainville, CT · Dissolved | Plainville, CT | Corporation | Apr 15, 1980 | Dissolved |
| ADVANCED COLLECTION SERVICES, LTD.Plainville, CT · Dissolved | Plainville, CT | Corporation | May 8, 1980 | Dissolved |